• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.4
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• pp.415-425
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• 1997

Although FHSS has many advantages over conventional digital radio communication system, field application has been so far hampered due to its complicated synchronization. In this paper, a new FHSS system is proposed which one FH signal modulated with GMSK and one chip delayed FH signal than former are sent from transmitter, and this is recovered by matching process at a heterodyne correlator in receiver; thus eliminates synchronization as a whole. Through analysis and experiment, we assure that there is possibility in this. The exper- imental result from 915~929 MHz bandwidth with 31 chips is investigated in the environment of AWGN.

• Journal of Nutrition and Health
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• v.48 no.3
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• pp.236-247
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• 2015

Purpose: This study was conducted to investigate the nutrient intake and food variety in Korean adolescents. Methods: We analyzed 1,555 adolescents aged 12 to 18 years using data from the combined 2010~2012 KNHANES (Korean National Health and Nutrition Examination Survey). In this study, subjects were divided according to age group (12~14 y, 15~18 y). The nutrient intake, ND (nutrient density), food intake and food score from each food group, variety and food intakes of meals, DDS (dietary diversity score), and GMVFDO (grain, meat, vegetable, fruit, dairy and oil food group) were analyzed using data from the 24-recall method. Results: The results showed that the 15~18 age groupskipped breakfast significantly more often than the 12~14 age group (p < 0.0001). The 15~18 age group consumed significantly higher quantities of fat per 1,000 kcal compared to the 12~14 age group (p = 0.0069). Regarding food variety, the 15~18 age group showed a significantly higher intake (p < 0.0001) and score (p < 0.0001) from beverages than the 12~14 age group, whereas the 15~18 age group showed a significantly lower intake (p = 0.0084) and score (p = 0.0253) from milk than the 12~14 age group. In addition, DDS in the 15~18 age group (4.33) tended to be lower than that of the 12~14 age group (4.44) (p = 0.0727). Conclusion: Proper dietary management regarding meal variety is needed for the 15~18 age group, and more systematic studies to investigate the meal variety roles of adolescents are required.

• Journal of the Korean Applied Science and Technology
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• v.32 no.2
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• pp.326-329
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• 2015

This study is to develop the double capsulation technology in order to increase the conservativeness and stability of unstable materials such as vitamins, polyphenols, natural active ingredients. And also, best way of triple matrix capsulation using natural polymers were detail described. As the first capsulation with w/o/w (water-in-oil-in-water) emulsifying system, our study group was especially made to soft and moisture cream using 5wt% of sucrose ester emulsifier as first capsulation. Nutrient agents are squalane, camellia oil. Triple matrix capsulation was formed with the best stabilized bead type capsules when it blended of chitosan, algin, sodium-potassium alginate. The bead diameter size was about 2.0~4.5mm (mean diameter: 3.2mm). Activity of lactobacillus containing cream for depending on various pH variations showed that alkalinity ($pH=10.8{\pm}0.5$) condition was higher than acidity ($pH=4.2{\pm}0.2$) and neutrality ($pH=7.1{\pm}0.3$) conditions. After a month, it also was certified to the activity of lactobacillus in incubated at $37{\pm}1^{\circ}C$ in culture medium. As application of food industry, we developed the containing lactobacillus capsule and 7 colored kinds of double and triple matrix capsulation in yogurt cream and active ingredients. As for above mentioned those results, one of tool to stabilize the living lactobacillus, doubled matrix capsulation greatly be expected to contribute to food industry. Furthermore, it can be expected to apply the drug delivery system (DDS) to active ingredients of stabilizing technologies at drug, pharmaceutical division and cosmetic industry, etc.

• The Korean Journal of Food And Nutrition
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• v.29 no.4
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• pp.456-464
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• 2016

The purpose of this study was to compare the quantitative and qualitative assessment of dietary intake between patients with metabolic syndrome (MetS) and healthy subjects and to investigate dietary factors related to MetS. Anthropometric measurements, blood analysis, and dietary intake as assessed by 24-hour recall were conducted in MetS patients (n=15) and healthy subjects (n=25). In order to assess the quantity and quality of dietary intake, daily nutrient intake, nutrient density, nutrient intake to dietary reference intake (DRI), nutrient adequacy ratio (NAR), food intake, dietary diversity score (DDS), and dietary variety score (DVS) were analyzed. The statistical differences between MetS patients and controls were analyzed using the SAS software program. Daily energy intake and food intake were not significantly different between the two groups (2,154.3 kcal vs. 1,872.9 kcal; 1,280.0 g vs. 1,261.6 g). There were also no significant differences in daily nutrient intake, nutrient intake ratio to DRI, NAR, or DVS between the MetS group and the control group. However, daily intake of eggs and milk in MetS patients was significantly lower than in the control group (9.0 g/day vs. 30.3 g/day, p<0.05; 0 g/day vs. 49.7 g/day, p<0.05). These results indicate that low intake of eggs and dairy products may be related to the development of MetS.

• Journal of Nutrition and Health
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• v.34 no.5
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• pp.568-579
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• 2001

This study was conducted to identify the characteristics of Korean diet in the view of food and food group intakes. The study subjects consisted of preschool children(PC), elementary school children(EC), high school students(HS), college students(CS), and adults over 30 years old living Seoul and the surrounding areas. The subjects over 30 years old were classified to 30-49 years, 50-69 years, and over 70 years. A dietary survey was conducted using 24-hour recall method and data were collected from 2392 subjects. Rice was a major contributor to many nutrients intake because of the amount of consumption. Vegetable oil made great contribution to fat intakes and eggs, squid, and anchovy supplied much cholesterol compared to other foods in all the age groups. Milk was major contributor of fat and cholesterol as well as calcium in younger age group, and seasoning gave much contribution to iron intakes. Mean dietary variety score(DVS) was 32 for EC group and 17 for subjects over 70 years, and tended to decrease along the increasing age. EC group consumed most variable number of foods of all groups but they consumed many junk foods, therefore the MAR value was low despite their high DVS value. Mean dietary diversity score(DDS) of each age group from PC group to subjects over 70 years was 4.34, 4.28, 3.79, 3.89, 3.76, 3.56, and 3.25, respectively. Food group, which was consumed below the minimum amount, was mainly fruits in all the age groups, and many subjects in HS group and over 30 years consumed dairy products below the minimum amount. From these results, age specific nutritional problems were found. PC group and subjects over 50 years seemed to need more diverse food intake than now, EC group did nutrient dense food, and HS group and subjects over 30 years did dairy products. Also, subjects took various nutrients from rice and seasoning contributed to some nutrients intakes. (Korean J Nutrition 34(5) : 568∼579, 2001)

• Nutrition Research and Practice
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• v.10 no.3
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• pp.294-304
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• 2016

BACKGROUND/OBJECTIVES: Eating out has been reported to have negative effects on nutritional status. However, eating out can include meals prepared at home and eaten outside. Conversely, meals eaten at home can be brought from outside, as take-out and home deliveries have become common in Korea. Thus, we tested whether or not meal preparation location influences daily diet quality. SUBJECTS/METHODS: From the Korea National Health and Nutrition Examination Survey (KNHANES) 2007-2009, 4,915 Korean adults (20-64 years) were classified into two groups: home-made meal group (HMG), who ate ${\geq}2$ meals per day prepared at home (n = 4,146), and non-home-made meal group (NHMG), who ate ${\geq}2$ meals per day prepared outside home (n = 769). Daily diet quality was determined by energy intake, nutrient intake, Dietary Variety Score (DVS), and Diet Diversity Score (DDS). RESULTS: Compared to the HMG, the NHMG was more likely to consist of men, single, employed, educated and of a higher economic status (all, P < 0.01). The NHMG showed higher energy intakes (1,776 vs. 2,116 kcal/day) with higher percentages of energy from protein (15 vs. 23%) and fat (14 vs. 16%) and lower intakes of dietary fiber, phosphorus, potassium, niacin, and vitamin C (all, P < 0.01) than the HMG, with some variations among age groups. The NHMG tended to consume foods prepared by frying and grilling and had more one-dish meals such as bibimbap, noodles, and dumplings but also showed higher dietary diversity. CONCLUSIONS: It should be noted that home-made meals do not necessarily guarantee a healthy diet, and the effects of meal preparation location on nutritional status might vary depending on socio-demographic characteristics.

• Journal of Nutrition and Health
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• v.40 no.4
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• pp.347-361
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• 2007

The purpose of this study was to analyze and evaluate dietary intake between with and without hypertension. Study subjects were more than 30 years old adults (n = 3,806) who participated in the 2001 Korea National Health and Nutrition Examination Survey. People who have 'self-recognition about hypertension' and 'having diet for hypertension' were excluded. Using the WHO standard, subjects were divided into the hypertensive group (SBP> 140, DBP> 90) and the normal group (SBP< 140, DBP< 90). The Body Mass Index (BMI) and the Waist-Hip Ratio (WHR) of a hypertensive group were higher than those of a normal group (p < 0.01). The distribution of the subjects for smoking, alcohol consumption, exercise, stress, preference of salty food were not significantly different between a normal group and a hypertensive group (p>0.05). Dietary intakes were investigated by the 24-hour recall method. When food and dish intakes analyzed by sociodemographic factors, normal group consumed more fruits than those of a hypertensive group. Statistical significant were shown at female group, residences in metropolitan area and having elementary school education (p<0.05). Hypertensive group consumed more alcoholic beverages than those of a normal group at 'age 39-39', 'aged 50-64', 'high economic status', 'low economic status' and 'residences in metropolitan' (p<0.05) The amount of intakes for fat, potassium, thiamin, vitamin C and alcohol were significantly different between the normal group and the hypertensive group (p<0.05). The highest score of the Dietary diversity score (DDS) was 4 in both normal group and hypertensive group. Normal group showed high Nutrition Density (ND) of vitamin C and hypertensive group showed high ND of sodium. In summary, these results showed that significant difference for people with hypertension were intakes of fruits, alcohol, thiamin, vitamin C. And these results differed by sociodemographic groups. Therefore, the differential approach in each group is demanded for prevention and control of the hypertension.

• Polymer(Korea)
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• v.25 no.2
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• pp.246-253
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• 2001

Amino terminated PES-CTBN-PES triblock copolymer was synthesized from PES oligomer and commercial CTBN rubber (CTBN1300$\times$13), and molecular weight of the copolymer was controlled to be 15000 g/mole. The copolymer was utilized to toughen diglycidyl ether of bisphenol-A (DGEBA) epoxy resin which was cured with 4,4'-diaminodi-phenylsulfone (DDS) and subjected to the measurement of thermal properties, fracture toughness ( $K_{IC}$), flexural properties and solvent resistance. The properties were compared with those from the samples modified by CTBN/PES blends. The maximum loading of copolymer into the epoxy resin was 40 wt% without utilizing solvent, at which $K_{IC}$ fracture toughness of 2.21 MPa${\cdot}m^{0.5}$ was obtained without sacrificing flexural properties and chemical resistance. However, the epoxy resin modified with PES/CTBN blend exhibited much lower $K_{IC}$ and flexural properties compared to the epoxy resins toughened by PES-CTBN-PES copolymers.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.2
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• pp.119-125
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• 2022

In this paper, we present design, implementation and test results of CTM (Chirp Transceiver Module) EM (Engineering Model) for C-Band SAR (Synthetic Aperture Radar) Payload. The CTM is designed to operate dual frequency scan method that simultaneously operate two frequencies in each 50MHz bandwidth to achieve 120Km swath with 10m resolution at about 500Km altitude. The CTM used radiation tolerant RTG4 FPGA for space environment, and implemented with the Parallel DDS (PDDS) method which uses a small memory capacity compared to the memory-map method. Test results show high purity chirp signal generation and excellent IRF performance from received chirp signal after direct digital conversion.

• Journal of the Korean Applied Science and Technology
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• v.30 no.4
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• pp.656-663
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• 2013

This study using yogurt of food in order to increase the conservativeness and stability of lactobacillus, to be deliciously flavored and give it visual differential effect, were described regarding making the preparing method of double matrix capsulation in food industries. Our study group was especially made to soft and moisture cream using 5wt% of sucrose ester emulsifier as first capsulation. Double matrix capsulation was formed with the best stabilized bead type capsules when it blended 1:3 ratio of chitosan and alginate. The bead diameter size was about 2.5~4mm (mean diameter: 3mm). Activity of lactobacillus containing cream for depending on various pH variations showed that alkalinity ($pH=10.3{\pm}0.3$) condition was higher than acidity ($pH=4.3{\pm}0.3$) and neutrality ($pH=7.12{\pm}0.2$) conditions. After a month, it also was certified to the activity of lactobacillus in incubated at $37^{\circ}C$ in culture medium. As application of food industry, we developed the containing lactobacillus capsule and 5 colored kinds of double matrix capsulation in yogurt cream. As for above mentioned those results, one of tool to stabilize the living lactobacillus, doubled matrix capsulation greatly be expected to contribute to food industry. Furthermore, it can be expected to apply the drug delivery system (DDS) to active ingredients of stabilizing technologies at drug and cosmetic industries.